/*
 * runon.c - assign a process to a named processor
 *
 * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 * 
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * 
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 * 
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
 * 
 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
 * Mountain View, CA  94043, or:
 * 
 * http://www.sgi.com 
 * 
 * For further information regarding this notice, see: 
 * 
 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
 */

#include	<stdio.h>
#include	<unistd.h>
#include	<linux/prctl.h>

#define _POSIX_OPTION_ORDER

static void usage();

int main(argc, argv)
int argc;
char *argv[];
{
	extern	errno;
	extern	__const char *__const sys_errlist[];
	int	c, processor, pid;
	int usepid = 0;
	register char *p;

	if (argc < 3) {
		usage();
		exit(1);
	}

	while ((c = getopt (argc, argv, "p:")) != -1) {
		switch(c) {
		case 'p':
			usepid = 1;
			pid = atoi(optarg);
			break;
		}
	}

	p = argv[optind];
	while(*p) {
		if(!isdigit(*p)) {
			fprintf(stderr, "%s: cpu argument must be numeric.\n", argv[0]);
			exit(2);
		}
		p++;
	}
	processor = atoi(&argv[optind][0]);
	optind++;

	if (usepid) {
		if (prctl(PR_MUSTRUN_PID, processor, pid, 0, 0) < 0) {
			fprintf(stderr, "%s: could not attach pid %d to processor %d\n",
										 argv[0], pid, processor);
			exit(1);
		}
	}
	else {
		if (prctl(PR_SET_RUNON, processor, 0, 0, 0) < 0) { 
			fprintf(stderr,
				"%s: could not attach to processor %d -- %s\n ",
				argv[0], processor, sys_errlist[errno]);
			exit(1);
		}
	
		execvp(argv[optind], &argv[optind]);
		fprintf(stderr, "%s: %s\n", sys_errlist[errno], argv[optind]);
		exit(1);
	}
	return(0);
}

static void usage() {
	fprintf(stderr, "usage: runon processor (-p pid | command [args...])\n");
}